1. Field of the Invention
The present invention relates to a silicophosphate-based phosphor and a light-emitting device (“LED”) including the same, and more particularly, to a silicophosphate-based phosphor having a high luminous efficiency and a high color rendering property and a LED including the same.
2. Description of the Related Art
White LEDs using semiconductors have a longer lifetime and lower operating voltage and can be more easily miniaturized than white electric lamps. Due to these advantages, white LEDs, as an alternative light source to white electric lamps, have a wide range of illumination applications, such as fluorescent lamps for home use or back lights of liquid crystalline display devices.
White LEDs can be obtained by using various methods. For example, three LEDs respectively producing red, green, and blue, which are the three primary colors of light, can be combined to produce white light. Alternatively, a yellow phosphor can be excited using a blue LED as a light source to generate white light. Alternatively, red, green, and blue phosphors can be excited using an ultra violet (“UV”) LED as a light source to generate white light.
In particular, the third method described above can be used at a high operating current, and the obtained color quality is good. Consequently, research into this method is actively being conducted.
When white LEDs are provided as described above, red phosphors that can be used are K5EU2.5(WO4)6.25, La2O2S:Eu, or the like; green phosphors that can be used are (Ba,Sr)2SiO4:Eu, or the like; and blue phosphors that can be used are Sr5(PO4)3Cl:Eu, or the like.
However, red phosphor exhibits a low luminous efficiency. As a result, a red phosphor having high luminous efficiency needs to be developed to produce a white LED having high efficiency and a high luminous efficiency.